Injector-impeller pump



Dem 1948- K. R. LUNG INJECTOR'IMPELLER PUMP Filed June 27, 1945 PatentedDec. 28, 1948 UNITED STATES PATENT OFFICE INJECTOR-IMPELLEB PUMP KennethR. Lung, Kendallville, Ind., assignmto Flint & Walling Manufacturing Co.Inc., Kendallville, Ind., a corporation of Indiana Application June 27,1945, Serial No.- 601,872

6 Claims.

This invention relates to features of widening the range of use ofimpeller type of rotary pumps, more particularly in association with avariable injector or jet type of pump.

This invention has utility when incorporated with a rotary pump, whereinthere is an injector primary stage provided with a jet-control effectedby the difierential between the delivery pressure of the second stagerotary pump and the supply pressure or suction to the primary pumpstage.

Referring to the drawings:

Fig. l is a side elevation of an embodiment of the invention as anautomatic pumping unit for maintaining in a particular range waterpressure tank, the pump being electrically operated in drawing waterfrom awell;

Fig. 2 is an enlarged section on the line 11-11, Fig. 1, showing thedetails of the diaphragmoperated needle valve for the venturi of theinjector' stage pump; and

Fig. 3 is a fragmentary showing of an adaptation wherein the needlevalve be not axially of the impeller stage pump, but may be remotetherefrom, as in the shaft to a water well.

An electric motor I has axially aligned therewith an impeller type ofrotary pump 2 in a housing 3, mounted on a common base 4 with themounting for the motor I. A riser line 5 from a water well has adischarge or port 6 into the housing 3. From the top of the housing 3,the pumped water from the well is conducted by a pipe I to a storagetank 8. From a port 9 in the housing 3 pulsations may act thru a ductIII to operate a diaphragm type of'air pump it to introduce air as acushion in the upper portion of the tank 8, thereby the better to holdthe pressure upon water withdrawals. The compressibility of the airmakes possible intermittent operation of the pump unit in holding thetank pressure within a desired range.

A pressure delivery chamber l2 from the impeller pump 2, has, inaddition to the take-off flow pipe I, a port l3 having a duct it,extending to a manually set or adjusted pressure responsive control orelectric switch l5. This automatic control may be set for cutting offthe motor 5 as the pressure in the tank 8 reaches 40 lbs. per sq. in.,with a cutting back of the motor to start at once the pressure in thetank falls to 20 lbs. per sq. in.

Axially of the impeller pump 2 and directed theretoward is acontinuously open Venturi nozzle is having a throat i with a convex zoneentrance it to the throat it. As this pump unit is intermittentlyoperated, at each starting, there is a pull or suction in a continuouslyopen way or passage ts from the port 9 leading to the zone It and thethroat II. This means a pump stroke at the pump ll acts to put air intothe tank 8.

Additionally there is communication by passage portions 20, 2|, from theport 6 to the zone 18 and the throat I'I. Besides outflow .by the pipeI, the pressure control by the pipe or duct l4, there is from thepressure chamber l2, in the housing 3 a jet or tapered nozzle 22 havinga continuously open discharge port 23 axially of the Venturi nozzle l6and its coaxial throat l1 and entrance zone Hi.

In developing the two-stage unit of injector or jet and rotary impellerpump, importance has resided in proportioning the continuouslyopenpressure supply jet nozzle port 23 diameter to be of six tenths toseven tenths of the diameter of the throat I1, over a range of pressuredrop from no water delivery to a maximum number of gallons of water perhour, short of cavitation. It is to be noted that the relation betweenthe diameters of the port 23 and the throat I! establishes that the areaof the port 23 is in the range of 36% to 49% of the area or crosssection or the throat ll, upon the fact basis that with like linealdimensions the effective area relation is to be taken as the squarethereof.

Under the invention herein, as the suction be decreased, the number ofgallons per hour may be increased, and with a marked decrease in thepower demand to achieve such as beyond the initial cavitation. To bringthis about, the efiective area of. the nozzle port 23 is modified. Thiscontrol factor is introduced automatically. A needle valve or stem 24coaxial with the tapered nozzle 22 is shifted by a diaphragm 25 to varythe maintained clearance relation of the convex contour of the member 24as to the opening 22.

Bolts 26 clamp housing axial terminal section 2? to the housing mainportion 3 to hold the flexible diaphragm 25 therebetween. Between thediaphragm 25 and the section 21 there is thus formed a chamber 28 incommunication by a passage 29 and thru an opening 30 in the clampedportion of the diaphragm 25 with a passage 3 in communication with thesuction passage portion 26. A compression helical spring 32 in thechamber 28 tends yieldably to thrust the needle member 2a to protrude inan effective area reduction position as to the port 23. In the housing$3 on the other side of the diaphragm 25 from the chamber 28, is achamber 33 in the housing 3!. A partition guide 3% provides a slidewayfor a stem 35 from the head or member 2%,

A head or enlargement 36 on the guide nut 34 provides a stop in thechamber 33 for the diaphragm 25, thereby precluding any shifting of theelement or member 24 to fully close the port 23.. The rod or stem 35 forthe member 24. as protruding thru the diaphragm 25 and passing axiallyof the spring 32, may .be centered and is freeto slide in and out of atubular boss 31 axially from the housing section 21. A port 38provides'communication from the pressure chamber l2 to the chamber 33.As the pump unit opcrates, there is a decrease in the pressure in thechamber 28, and an increase in the pressure in the chamber 33. Thesetting of the yieldable means 32 is a control factor to determine therange of pressure differential required to develop automatically theadvantages of modification for the port 23 as to the throat ll.

Instead of locating the pump 2 in the housing 3, a housing 35 thru aduct39 may extend to a remote place, as into the shaft of a water welland there be connected thru the nozzle l6 and a housing 40 with theriser line or intake 5. A pressure chamber 4| .in the housing 39 (Fig.3)

has duct 42 to the housing 40 with a chamber .3

to the jet nozzle 22. Additionally in the housing 40 is a suctionchamber 44 to the zone l8.

From the lower portion of the chamber 44 there is a port 45 to a chamber46 in which is a bellows type diaphragm or partition 41. compressionspring 48 thrusts a shoulder 49 against a stop 50 in thereby limitingthe shift of a rod or stem 5! mounting the element or needle valve 24short of fully closing position as to the port 23. From the chamber 43there is a passage 52 along the stem 5| thru the guide-nut-providingstop 50 to a chamber 53 within the sylphon" or bellows 41. As thedifferential pressure between the chambers 43, 53, and the chambers 44,46, becomes greater, the spring 48 is compressed. This causes the member24 to be retracted in thereby automatically increasing the net effectivearea of the port 23. Resultantly, this means an increase in the numberof gallons to be pumped per hour.

More specifically, an example may be taken of a centrifugal stage pumpwith an injector booster stage therefor. Such a pump at lift forstarting may require 625 watts at initial or top pressure of 62# per sq.in. Therefrom it may have a pressure drop to 28# per sq. in. at 580gallons of water delivery per hour for this latter performance, a powerof 655 watts is to the limit where. cavitation begins. This unit atlift, at starting takes 635 watts to develop 58s pressure maximum withno delivery. At 420 gallons per hour it shows a pressure drop to 33# persq. in. and a power requirement of 645 watts cavitation follows atfurther delivery volume attempt. In this comparison, a third performancefigure is for lift, at which 640 watts will develop 57 4 pressure at nodelivery. A maximum delivery is of 305 gallons per hour at 32 1? and 650watts load. Under the automatic control from the total effective head,there is retraction of the needle 24. This leaves a greater effectivenozzle area at the port 23, for greater quantity of discharge liquidfrom the impeller pump to be recirculated thereto thru the Venturisection. This greater flow increases the suction action in the throatI8. The result is a higher pressure discharge and an increase inperformance efficiency of the booster. From this basis, it is to benoted that with the nozzle modification for reduced efiective area thereA helical 4 is less volume of liquid to pass and improved pumpefllciency at low pressure. Conversely a nozzle effective area increasegives greater liquid volume recirculated. This makes possible theimproved, pump efliciency at higher pressure.

The pattern for the advantages arising in this automatic pressureresponsive control in extending the useful range for pump operation isshown by figures on performance. With the spring 32 or 48 to provide aninitial location for the control of the reciprocable member 35 or SI forthe needle valve 24, the cavitation at 15' is moved over from 580gallons per hour delivery, to 830 gallons per hour, however, with thedelivery pressure now dropped to 17# per sq. in. In this connection theautomatic control is not a holdoff until cavitation at 580 gallons perhour, but has gradually slightly raised the pressure to show per sq. in.at 580 gallons per hour. or more importance still is the fact thatinstead of requiring 655 watts, the load is 5'70 watts; and at 830gallons per hour, 17# per sq. in., the load is down to 535 watts.

The figures for 20' suction, and the automatic control to decrease theeffective area of the nozzie 23 at the needle 24, does not havecavitation at 420 gallons per hour with 610 watts (instead of 645watts), at 33# per sq. in., and carries on thru to 20# per sq. in., 670gallons per hour at 510 watts power consumption.

Still more pronounced efficiency advantage follows in the instance of 25lift, which at 305 gallons per hour, at 36# pressure per sq. in.,requires 620 watts; while 470 gallons per hour, at 16# per sq. in.delivery pressure, to cavitation, take 460 watts.

From the foregoing performance data, it is to be noted that as theinjector pump approaches what had been cavitation, the pressureresponsive interduct control between supply and discharge functionsautomatically, slightly to build up the discharge pressure and with aquite material decrease in power consumption. The eiliciency on the 15lift is improved 31%; the 20 lift and the 25 lift 48%, on the basesabove set forth.

Details of the impeller as to the venturi are shown in Patent 2,274,987Lung, Mar. 3, 1942, Self-injector rotary pump.

What is claimed and it is desired to secure by Letters Patent is:

1. A rotary pump having an intake port, a tube discharging into saidintake port, said tube having an expanded end remote from said pumpconverging to a restricted throat, a supply passage for the pumpconnected to the expanded end of the tube, a nozzle having a portcoaxial with the tube and directed across said supply passage into saidexpanded'end of the tube, a needle valve centrally positioned in and'never completely closing said port, a suction chamber, a duct betweenthe chamber and the supply passage, an additional chamber, said pumphaving a discharge passage provided with a duct to the additionalchamber and to the needle valve side of the nozzle for flow dischargeabout the needle valve toward the throat, and pressure responsivecontrol, means coacting between the chambers, said means havingconnection therefrom to the needle valve to vary the effectivecross-sectional area for flow between the needle and port.

2. A rotary pump having an intake port and a discharge passage, aVenturi tube discharging into said intake port, said tube having anentrance, 9. supply passage for the pump directed to said entrance, anozzle directed across the supply passage and having a port coaxial withthe tube, a needle valve centrally of the port and at all timesmaintaining the port open, a pressure responsive control chamber havingdirect duct communication with the supply passage, an additional chamberhaving independent duct communication from the dischargepassage, saidduct having communication with the nozzle for flow therefrom about thevalve toward the throat, said duct communications being at all timesopen, pressure actuated means coacting with the chambers, and atransmission connection from the means to the needle valve to modify theflow area of the port.

3. A rotary pump having an intake port and a discharge passage, aVenturi tube discharging into said intake port, said tube having from anentrance thereto a restriction forming a throat, a supply passage forthe pump to said entrance, a pressure delivery chamber having a centralport nozzle therefrom directed coaxially of the tube across the supplypassage, a needle valve having flow spacing at all times thereabout asto the port, an additional chamber having direct duct communication withthe supply passage, independent duct communication from the dischargepassage to the delivery chamber, and transmission means coacting frombetween the chambers to shift the valve relatively to the port to varythe cross section of a flow stream into the tube throat in passing thenozzle in its flow course from the pump discharge passage.

4. A rotary pump having an intake port and a discharge passage, aVenturi tube in communication with said intake port, there being anentrance to the tube extending to a throat restriction, a supply passagefor the pump to said entrance, a member providing a pressure deliverychamber including a nozzle having a port directed across the supplypassage and coaxially of the tube, a needle valve mounted in the chamberand in thenozzle spaced from the port, an additional chamber havingdirect duct communication with the supply passage and also having amovable partition common with and spacing the additional chamber fromthe delivery chamber, and needle valve actuating means having connectionfrom the partition, whereby pressure change in the supply passagereacts, thru the partition as modified by the pump discharge pressure inthe pressure delivery chamber, for shifting the needle valve to changethe effective stream cross-section from the nozzle in thereby 6 coactingfor stream cross section change from the supply passage into the throat.

5. A rotary pump having an intake port and a discharge passage, aVenturi tube in commu nication with said intake port, there being anentrance to the tube inwardly tapering to a throat, a supply passage forthe pump to said entrance, a nozzle having a pressure delivery chambersupply thereto, said nozzle having a port in a range up to one half thecross-sectional area of the throat, said nozzle'directing said portacross the supply passage and coaxially of the throat, means for varyingthe eifective area of the port including a needle valve coacting at alltimes against fully closing the port, an additional chamber having ductcommunication with the supply passage, said delivery chamber having ductcommunication with the pump discharge passage, said duct communicationsbeing maintained open at all times during pump operation,

.and inter-chamber responsive control means connected to shift theneedle valve relatively to the port to vary the efiective cross-sectionof the port to leave the throat cross-sectional area relatively moregreat.

6. A rotary pump having an intake port and a discharge passage, aVenturi tube in communication with said intake port, there being anentrance to the tube extending to a restricted throat, a supply passagefor the pump to said entrance, a nozzle, a pressure delivery chambermounting the nozzle for discharge across the supply passage andcoaxially toward the throat, an additional chamber having ductcommunication with the supply passage, duct communication from thedischarge passage to the delivery chamber, a flexible diaphragm forminga par-' tition between the chambers, a valve needle in the nozzle, and amounting for the needle connected to the diaphragm to vary the effectivenozzle cross-section.

KENNETH R. LUNG.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

